Make the aïoli first. Crush the garlic in a pestle and mortar with salt until smooth. Transfer to a large mixing bowl and whisk in the yolks and lemon juice. While whisking very fast, slowly pour in the oil — a few drops at the beginning and increasing to a very slow stream. If instead of thickening you get a thin mixture with little droplets of oil, your mayonnaise has split. Don’t worry, just crack another egg yolk into a bowl and then slowly whisk the split mixture into the new egg yolk. Add a splash of water if it is too thick for your liking. Adjust the seasoning and keep chilled while you prepare the rest of the salad.

Place the white crabmeat in a bowl and stir in the chilli, parsley and lemon zest and season to taste. Put to one side.

Place the brown crabmeat in a bowl and squeeze in the lemon juice.

Season well and stir in three tablespoons of oil so that it is nice and loose and glossy. Put to one side.

Place the apples, fennel and watercress in a bowl and add the white crabmeat. Toss lightly with your hands, then transfer to a large serving plate or individual plates.